Foam cups reinforced by wrap-around labels are widely used as drinking cups, particularly for beverages served warm such as coffee. The foam cups, which are typically made of beaded polystyrene, are shaped for holding a liquid and exhibit good insulating properties. The wrap-around labels, which are typically made of paper or plastic film, reinforce sidewalls of the foam cups and provide good printing surfaces for applying text and graphics to the reinforced foam cups.
Sidewalls of the foam cups have a generally frusto-conical shape and the wrap-around labels are shaped to match the unrolled form of the frusto-conical shape. The wrap-around labels are generally attached to the foam cups with a pressure-sensitive adhesive that bonds the labels to the cups. Within a region of overlap, the pressure-sensitive adhesive bonds opposite ends of the wrap-around labels to each other.
Generally, the pressure-sensitive adhesive completely covers a back surface of the label to provide an uninterrupted bond with the underlying foam cup. The continuous bond between the wrap-around label and the foam cup can provide a smooth outer surface for displaying text and graphics. In addition, the smooth outer surfaces of the label-wrapped cups enable the cups to be collected into stacks and released individually from the stacks with a consistently low force. However, heating, cooling, stretching, or bending the sidewalls of the cups can produce unsightly wrinkles in the labels.
Pressure-sensitive label stocks can add cost to the label-wrapped cups because a release liner is required to protect the pressure-sensitive adhesive until the labels are in position for application to the cups. Once the pressure-sensitive labels are removed from the release liner, the release liner is discarded. As much as one-third of the cost of the pressure-sensitive label stocks is attributable to the release liners that form no part of the finished label-wrapped cups.